MTO不停车检修污水汽提塔降低净化水COD措施

Measures to Reduce Purified Water COD by No Parking Maintenance of Sewage Stripper

由于污水汽提塔压差高,导致传热传质效果变差,汽提效果变差,净化水中COD含量长期偏高,可达2726 mg/L,通过不降负荷不停车将污水送至事故罐的方法切除污水汽提塔并进行检修。检修后污水汽提塔压差为27 k Pa,通过适度降低污水汽提塔净化水的pH值为~8.0,控制污水汽提塔汽提气冷凝后温度至少为100℃,合适的污水汽提塔塔顶操作压力,定期清理污水汽提塔塔顶回流泵过滤网等工艺措施降低了净化水中的COD至300 mg/L以下。

Due to the high pressure difference in sewage stripper,the effect of heat and mass transfer got worse and stripping got worse,either.The content of COD in the purified water was high for a long time,up to 2726 mg/L.Sewage stripper was closed off and maintained by keeping methanol flow,no parking and sending sewage to accident tank.After maintaining,the pressure difference was 27 kPa in the sewage stripper.The COD in purified water was reduced to below 300 mg/L by these process measures:purified water pH of^8.0 in sewage stripper,gas condensation temperature of at least 100℃,the optimum operating tower top pressure,and regular cleaning of sewage stripping tower top reflux pump filter.